2. Description of the Related Art
Over the past number of years, digital cameras have begun to replace more conventional film camera. Digital cameras employ electronic devices, or “imagers,” to capture a picture by using electronic components. Originally, the technology of electronic image capture employed charged-coupled devices (CCDs) in products such as a television camera in 1975 and an observatory telescope in 1979. In 1982, the first solid state personal camera using CCDs was introduced.
A low cost and more commonly available electronic component that is suitable for imagers is a complementary metal oxide semiconductor (CMOS) sensor. One advantage of CMOS sensors is that, unlike CCD technology, other circuits such as those required for error correction, image stabilization, image compression and image enhancement may be incorporated in the same chip. In addition, a single chip design typically requires less power than a multiple chip design, thus increasing battery life.
Typically, a picture produced by all but the most expensive digital camera does not have as fine a resolution as the more traditional film-based cameras. CMOS imager sensors included in digital cameras are fabricated as a two-dimensional array of millions of pixels. Until now, the only way to increase the resolution of the pictures the digital camera produces is to increase the number of pixels. Of course, increasing the number of pixels also increases the cost and complexity of the imager.